Senior Backend Engineer · Wrocław, Poland

Systems built to last

I build the backend systems that make products work - reliable, scalable, ready for production. 7 years of experience, from architecture to delivery. Got a project? Let's talk.

Get in touch → LinkedIn

About

Maciek Bartosik

By day I work on a large distributed backend - microservices, gRPC, GCP, observability at scale. By night I'm building TutAll, a SaaS platform for tutors, which means I think about systems from both sides: engineering and product.

I'm an early adopter of AI-assisted development - I use Claude Code daily and actively promote that workflow across my team. In practice: faster delivery, fewer rabbit holes, better code.

If you have a backend challenge that needs senior attention - let's talk. I work best when I can own a problem end-to-end.

Tech stack

Go / GolangMicroservicesgRPCGCPReactClaude CodeAI-assisted dev PostgreSQLPrometheusGrafanaOpenTelemetryGitLab CIDockerREST APIsKubernetes

What I bring

⚙️
Backend architecture
Multiple microservices, millions of requests per day, designed for scale.
🤖
AI-powered workflow
Faster delivery with Claude Code and AI-assisted development.
🔍
Observability
P99 latency tracking, distributed tracing across services.
🧭
Senior review
Code quality gates, architecture decisions, mentoring.

Availability

Commitment
up to 20h / week
Format
Remote · B2B
✦ Open to ongoing contracts as well as one-off projects

Projects & highlights

TutAll
SaaS platform for tutors - lesson management, AI-powered transcription, homework generation, payments. Architected and built end-to-end: Go backend on GCP (Cloud Run, Cloud SQL, Vertex AI), React frontend.
tutall.app ↗
Release automation bot
Slack bot that automates the entire release process - changelog generation, version tagging, production deploys, team notifications. Replaced a manual workflow that used to take 30+ minutes per release.
API Gateway
Built from scratch as a proxy layer for all external API calls. Identified caching opportunities that significantly reduced response times across dependent services.
Observability stack
Set up the full monitoring stack from zero - distributed tracing, context-aware logging, metrics dashboards. Now the first thing the team reaches for during incidents.
Data pipeline optimization
Identified bottlenecks through traces and metrics in a data processing pipeline. Redesigned for parallel execution - significant throughput improvement.
Claude Code workflow
Custom Git automation built around Claude Code - pre-commit hooks, branch management, slash commands for PR creation and code review. Daily driver for AI-assisted development.
Messaging integrations
Built Instagram and Telegram messaging integrations for LiveChat - webhooks, media handling, OAuth, real-time message delivery. The unglamorous work that makes products talk to each other.

Let's talk.

// part-time · remote · B2B

maciek@bartosik.wtf +48 530 811 093 or Book a call →